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Full-Text Articles in Physics
Residual Optical Absorption From Native Defects In Cdsip2 Crystals, Timothy D. Gustafson, Nancy C. Giles, Elizabeth M. Scherrer, Kevin T. Zawilski, Peter G. Schunemann, Kent L. Averett, Jonathan E. Slagle, Larry E. Halliburton
Residual Optical Absorption From Native Defects In Cdsip2 Crystals, Timothy D. Gustafson, Nancy C. Giles, Elizabeth M. Scherrer, Kevin T. Zawilski, Peter G. Schunemann, Kent L. Averett, Jonathan E. Slagle, Larry E. Halliburton
Faculty Publications
CdSiP2 crystals are used in optical parametric oscillators to produce tunable output in the mid-infrared. As expected, the performance of the OPOs is adversely affected by residual optical absorption from native defects that are unintentionally present in the crystals. Electron paramagnetic resonance (EPR) identifies these native defects. Singly ionized silicon vacancies (V-Si) are responsible for broad optical absorption bands peaking near 800, 1033, and 1907 nm. A fourth absorption band, peaking near 630 nm, does not involve silicon vacancies. Exposure to 1064 nm light when the temperature of the CdSiP2 crystal is near 80K converts …
Enhancing The Visibility Of Vernier Effect In A Tri-Microfiber Coupler Fiber Loop Interferometer For Ultrasensitive Refractive Index And Temperature Sensing, Fangfang Wei, Dejun Liu, Zhe Wang, Zhuochen Wang, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova
Enhancing The Visibility Of Vernier Effect In A Tri-Microfiber Coupler Fiber Loop Interferometer For Ultrasensitive Refractive Index And Temperature Sensing, Fangfang Wei, Dejun Liu, Zhe Wang, Zhuochen Wang, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova
Articles
In this paper a Vernier effect based sensor is analyzed and demonstrated experimentally in a tri-microfiber coupler (Tri-MFC) and polarization-maintaining fiber (PMF) loop interferometer (Tri-MFC-PMF) to provide ultrasensitive refractive index and temperature sensing. The main novelty of this work is an analysis of parameters of the proposed Tri-MFC-PMF with the objective of determining the conditions leading to a strong Vernier effect. It has been identified by simulation that the Vernier effect is a primary factor in the design of Tri-MFC-PMF loop sensing structure for sensitivity enhancement. It is furthermore demonstrated experimentally that enhancing the visibility of the Vernier spectrum in …
Birefringent Optofluidic Gratings, Sergio Calixto, Jose L. Garcia-Cordero, Diana F. Cedillo-Alcantar, Izabela Naydenova, Guillermo Garnica
Birefringent Optofluidic Gratings, Sergio Calixto, Jose L. Garcia-Cordero, Diana F. Cedillo-Alcantar, Izabela Naydenova, Guillermo Garnica
Articles
A set of parallel microfluidic channels behaving as a diffraction grating operating in the Raman-Nath regime has been fabricated and studied. The diffraction efficiency of such structure can be tuned by selecting a liquid with a particular refractive index and/or optical anisotropy. Alternatively the optical properties of the liquid can be characterised by measuring the diffraction efficiency and the state of polarization of the diffracted beam. In this work, the microfluidic channels under study have been filled with penicillin molecules dissolved in water. Due to the chirality of the penicillin, the liquid has been found to have circular birefringence of …
Index Of Refraction From The Near-Ultraviolet To The Near-Infrared From A Single Crystal Microwave-Assisted Cvd Diamond, Giorgio Turri, Scott Webster, Ying Chen, Benjamin Wickham, Andrew Bennett, Michael Bass
Index Of Refraction From The Near-Ultraviolet To The Near-Infrared From A Single Crystal Microwave-Assisted Cvd Diamond, Giorgio Turri, Scott Webster, Ying Chen, Benjamin Wickham, Andrew Bennett, Michael Bass
Publications
The refractive index of a type IIa CVD-grown single-crystal diamond was measured by ellipsometry from the near ultraviolet to the near infrared region of the spectrum. As a consequence, a one term Sellmeier Equation with coefficents of B-1 = 4.658 and C-1 = 112.5 for the refractive index of diamond, for the wavelength range from 300 to 1650 nm, was derived that is only as accurate as the input data, +/- 0.002. The experimental results in this paper between 800 and 1650 nm are new, adding to the values available in the literature.
Evaluation Of Ray-Path Integrals In Geometrical Optics, John A. Adam, Michael Pohrivchak
Evaluation Of Ray-Path Integrals In Geometrical Optics, John A. Adam, Michael Pohrivchak
Mathematics & Statistics Faculty Publications
A brief summary of the physical context to this paper is provided, and the deviation angle undergone by an incident ray after k internal reflections inside a transparent unit sphere is formulated. For radially inhomogeneous spheres (in particular) this angle is related to a ray-path integral; an improper integral for which there are relatively few known exact analytical forms, even for simple refractive index profiles n(r). Thus for a linear profile the integral is a combination of incomplete elliptic integrals of the first and third kinds (though not all are as complicated as this). The ray-path integral is evaluated …
Optical And Thermal Properties Of Spinel With Revised (Increased) Absorption At 4 To 5 Μm Wavelengths And Comparison With Sapphire, Daniel C. Harris, Giorgio Turri
Optical And Thermal Properties Of Spinel With Revised (Increased) Absorption At 4 To 5 Μm Wavelengths And Comparison With Sapphire, Daniel C. Harris, Giorgio Turri
Publications
Infrared absorption of high-quality, commercial, polycrystalline MgAl2O4 spinel is ∼40% greater in the range of 3.8 to 5.0 μm than the value predicted by the computer code OPTIMATR®, which has been used for window and dome design for more than 20 years. As a result, spinel and a-plane sapphire windows designed to support the same external pressure with the same probability of survival have approximately the same infrared absorptance in the range 3.8 to 5.0 μm. c-Plane sapphire has greater absorptance than spinel in the range 3.8 to 5.0 μm. Spinel has two weak absorption bands near 1.8 and 3.0 …
Optical And Holographic Characteristics Of Photopolymer Layers, Temenujka Yovcheva, Izabela Naydenova, Ivanka Vlaeva, Suzanne Martin, Vincent Toal, Simeon Sainov
Optical And Holographic Characteristics Of Photopolymer Layers, Temenujka Yovcheva, Izabela Naydenova, Ivanka Vlaeva, Suzanne Martin, Vincent Toal, Simeon Sainov
Articles
In the present work the optical and holographic characteristics of acrylamide-based photopolymer layers are studied. For the first time the refractive index change of a liquid acrylamide photopolymer due to exposure at 532 nm is obtained using a critical angle laser micro-refractometer. The 30 mm thick solid photopolymer films are prepared by casting on glass substrates. Bragg holographic gratings with spatial frequencies of 710 mm-1, 1050 mm-1 and 1600 mm-1 are recorded using a diode laser operating at 532 nm wavelength. The diffraction efficiency dependence on the exposure energy is investigated. The obtained results are compared with the Stetson holographic …
Terahertz Studies Of The Dielectric Response And Second-Order Phonons In A Gase Crystal, B. L. Yu, F. Zeng, V. Kartazayev, R. R. Alfano, K. C. Mandal
Terahertz Studies Of The Dielectric Response And Second-Order Phonons In A Gase Crystal, B. L. Yu, F. Zeng, V. Kartazayev, R. R. Alfano, K. C. Mandal
Faculty Publications
No abstract provided.
A Simple Design For An Electronic Speckle Pattern Interferometer, Thomas R. Moore
A Simple Design For An Electronic Speckle Pattern Interferometer, Thomas R. Moore
Faculty Publications
An electronic speckle pattern interferometer suitable for use in an undergraduate laboratory is described. This interferometer can be built for a small fraction of the cost of a commercial version and is simple and inexpensive to build and understand. The interferometer is useful for visualizing the normal modes of vibrating objects as well as changes in index of refraction.
Comparative Analysis Of Bragg Fibers, Shangping Guo, Sacharia Albin, Robert S. Rogowski
Comparative Analysis Of Bragg Fibers, Shangping Guo, Sacharia Albin, Robert S. Rogowski
Electrical & Computer Engineering Faculty Publications
In this paper, we compare three analysis methods for Bragg fibers, viz. the transfer matrix method, the asymptotic method and the Galerkin method. We also show that with minor modifications, the transfer matrix method is able to calculate exactly the leakage loss of Bragg fibers due to a finite number of H/L layers. This approach is more straightforward than the commonly used Chew’s method. It is shown that the asymptotic approximation condition should be satisfied in order to get accurate results. The TE and TM modes, and the band gap structures are analyzed using Galerkin method.